Stanley Druckenmiller earned his reputation as a top investor (and earned much of his billionaire status), working with legendary investor George Soros from 1988 until 2000.

Their most celebrated bet was against the British pound in 1992. They “broke the Bank of England,” as commentators put it, reportedly earning a cool $1 billion.

After he left Soros, Druckenmiller managed his own hedge fund, Duquesne Capital. In 2011, he switched to a family office – Duquesne Family Office. His successful track record has investors eager to learn his moves in the market.

While we don't have Druckenmiller on speed dial, his family office is required to file a 13F report with the Securities and Exchange Commission every quarter detailing his holdings.

Amazon is an e-commerce and AI kingpin

Alphabet  (GOOG)  and Amazon  (AMZN)  represent two mega-cap tech stocks that have been in Duquesne’s portfolio.

Related: Billionaire George Soros sold this popular semiconductor stock

Amazon is the top online retailer and cloud service provider in the world. Its cloud unit is called Amazon Web Services, or AWS. AWS's widespread use by companies to store, parse, and analyze data means it's at the center of efforts to train and run artificial intelligence solutions.

“Amazon dominates its served markets, notably for e-commerce and cloud services,” wrote Morningstar analyst Dan Romanoff.

In addition, Amazon’s advertising business is already big and continues to grow as ads have made their way into Amazon’s streaming outlets, Romanoff noted.

Amazon’s fourth-quarter earnings numbers impressed analysts, beating Wall Street forecasts.

Net income rocketed to $10.6 billion, or $1 a share, from $278 million, or 3 cents a share. Strong holiday sales helped boost the numbers.

AWS revenue grew 13%. While that figure didn’t blow analysts’ socks off after stratospheric gains in past years, it beat the 12% gains of the previous two quarters.

AWS's operating profit climbed 38%, and ad revenue ascended 27%.

Looking forward, Amazon forecasts revenue expansion of 8% to 13% this quarter from a year earlier. It also sees operating income increasing by 67% to 150%.

Alphabet's Google rides a wave of AI spending

Alphabet’s Google, of course, is the king of Internet search and has a strong cloud presence of its own, ranking third in market share (Microsoft is second).

Google's search incorporates its large language model, Gemini, while its cloud business similarly benefits from enterprise AI app training and use.

“Alphabet dominates the online search market with a 90%-plus global share for Google, and the business generates very strong cash flow,” wrote Morningstar analyst Ali Mogharabi.

“We expect continuing search growth. We remain confident that Google will maintain its leadership, despite Microsoft moving first to include artificial intelligence in Bing search.”

Alphabet’s YouTube video platform and Google Cloud also will boost the company’s fortunes, Mogharabi said.

But Alphabet’s fourth-quarter earnings disappointed investors. Ad revenue totaled $65.5 billion in the period. While that represented an 11% increase from a year ago, it lagged analysts’ estimate of $65.9 billion. Ads account for about 75% of Alphabet’s overall revenue.

To be sure, the fourth-quarter numbers weren’t all bad. Overall revenue registered $86.3 billion, up 13% from a year earlier. Analysts expected $85.3 billion. Revenue growth has accelerated for each of the last four quarters.

And net income hit $20.69 billion, or $1.64 a share, in the fourth quarter, up from $13,62 billion, or $1.05 per share, a year ago. The latest per-share figure beat Wall Street analysts’ prediction of $1.59.

Stanley Druckenmiller’s sells Amazon, Alphabet

We don’t know exactly what Druckenmiller thinks of the two companies. But we know that Duquesne sold all its Amazon and Alphabet holdings in the fourth quarter.

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That information came in the firm’s 13F report to the Securities and Exchange Commission.

Perhaps Druckenmiller believes the companies’ share prices have peaked, or perhaps he wanted to reduce his technology sector exposure.

Maybe he wanted to focus on his other AI stocks, including Nvidia. After all, he did buy Nvidia calls in the fourth quarter valued at $242 million, and combined with the 617,494 shares he owned, it was his largest position, accounting for over 16% of assets.

Last year, he said, “AI could be as innovative as the internet." So, it's not like he doesn't believe in AI's potential.

Whatever the case, Duquesne dumped 136,690 shares of Amazon in the fourth quarter, worth $20.9 million as of Dec. 31. The firm unloaded 838,375 shares of Alphabet, worth $117.1 million.

Alphabet’s shares have firmed 2% year to date, while Amazon stock has gained 12%.

The author of this story owns shares of Alphabet and Amazon.

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